Canadian nuclear plants emit 40 times more tritium every day when functioning normally than the Vermont Yankee leak emitted in a year:
A 1 GW(e) natural gas turbine will emit about 9 curies/year,* which is 20 times the rate of radiation from the VT Yankee leak at its highest.
Oh, and natural gas "fracking" produces toxic and radioactive wastewater. This article from last summer discusses EPA tests that found nasties from the fracturing fluid in domestic well water:
New York State is doing fracking in something called Marcellus shale. This article from last fall says that surface wastewater from these sites was found to contain Ra-226 in concentrations "thousands of times" the limit for drinking water:
says, "more than 18 billion barrels of waste fluids from oil and gas production are generated annually in the United States".
* Radioactivity of fossil gas. This abstract
gives 200 Bq/m^3. It doesn't say where they measured, but given context of the paper I'll assume it was at the consumer end of the line, at STP. I don't know if gas used at electrical plants is any fresher, but I'll assume it's no more stale. Pure methane has an energy content of 55.5 kJ/g and a density of 667 g/m^3, or about 5 Wh(e)/L from a 50%-efficient combined-cycle plant. So about 40Bq/Wh, or 1 nanoCurie per Wh, or 9 Curies/GW-yr.